Aegir

I wasn't having a real good day today, so I went for a cruise in my TL to lift my spirits. All was well until I got home and found a tire going flat. I pulled the wheel of and ran it up to the tire store to get fixed. When I got home, I decided to make the best of it and rotate my tires. When I got to the front left, I stared at the fenderwell and thought "Intake silencer, your time is up." :devil: I think I started with the intention of just scoping the job, but it was simple and quickly got serious.

Removal was straighforward. I pulled the fasteners for the front of the fender liner and pulled it back. There were four bolts that held the intake assembly in place. I had to drill out the two rivets between the bottom of the silencer and the tubing in order to remove them in two parts. I left the rubber 'donut' on the intake housing based on the recommendations I saw regarding second gen CL's on A-CL - thanks guys!

Here are a few pics:

Intake from above without silencer - looks stock huh? Even more so with all the shrouding reinstalled! The inlet location is still very high, so I expect no water problems.


Intake from below - nice clean shot, straight to the filter. No restrictions here!



Here's what was pulled out:



Finally, here's a shot of the intake silencer internals. Two ports top and bottom:


Driving impressions:
The car definitely seems to have more power above 5000 - the car was pulling noticably harder in the twisties, and it was a hot day today. I'm getting more wheelspin on my 1st to 2nd shift now as well. To all those who distrust the 'butt dyno', you are right to do so. I'd like to get the car dyno'd but no promises on how soon I can get to it.

Still nice and quiet idling and everyday cruising. No difference unless I'm on the gas - perfect. The sound at idle may be a bit deeper, but that could be my imagination. Big difference at higher RPM's. Around 3000 or so, heavy throttle results in a nice, deeper-toned growl. Above 5000 RPM, the car sounds wonderful - louder and a bit meaner. No weird or unpleasant sounds. I think it was a productive change, especially considering the cost - freebie!

Mylriahd

I may get brave enough to try this one day, I definitely would love a little more of the engine's tone.

By the way, I see your garage looks much like mine! Woodworking! I shoved everything into one side so I could park my TL, but that won't fly for long cause my wife still wants to park in th garage. Gotta get mobile bases fast.

dark inspire

oh man! well done. its about time u got taht taken out. next meet ur gonna be ROARing! crazy 3rd Genners' we've been doin it for years! hahah good one mike!

daikon38

Just curious as to the theoretical and "real-world" MPG implications for something like this.

Theoretically, would there be a MPG increase or decrease? Why?

"Real-world" MPG increase or decrease? Was it according to theory? If not, what factors may have affected it?

Just curious. Thanks.

neuronbob

Those are great pix, Aegir. Thank your for posting. This is another one for the "TL Garage"....Rets?

I would think that with the slightly freer airflow, this mod would lead to slightly increased gas mileage.

Road Rage

Resonators can actually improve midrange torque, by using Helmholtz resonance principles to tune the intake tract, just as the intake runners tune the air/fuel intake. It may sound different, but the driving effects are minimal at best. Indeed, I have seen engineering monographs at the SAE that Volvo provided where mid-range torque dropped, and fuel economy suffered a bit. A few ponies at the top of the RPM range may be useful if that is where yous pend 90% of your time, as in racing.

jackal2001

why not just get rid of the whole thing

http://www.coximport.com/aem/inductionapps.html
look for the 04 TL

flnsx

Hey!!!

Great write-up! You da man!

I have a couple questions for you.

You wrote "I had to drill out the two rivets between the bottom of the silencer and the tubing in order to remove them in two parts."

1. Does this mean you won't be able to put it back on now?

2. Can I remove mine without any drilling?

3 How do you think this effect the "RAM AIR" effect that we have with the resonator and tubs in place?

4. Do you think you are actually getting les air in at high speeds now due to you removing the ram air?

jackal2001

http://www.aempower.com/pdf/dyno/21-...Acura%20TL.pdf


sorry AEM says "coming soon" as it is not available yet???

JoganJani

Aegir, any changes in the sound? Any hissing?

Aegir

1. I can reinstall if I decide to - either based on future driving impressions or a future dyno (need to find a shop). The two pieces snap together, and the rivets could be easily replaced.
2. I think the whole assembly would come out as one piece if the front bumper was removed.
3. I don't think the old system provided a ram air effect, but it did duct cool air up to the inlet. The outlet of the duct from the bumper sat about five inches below and to the right of the inlet.
4. No, if anything the car is getting more air at higher RPMs. It feels noticibly stronger above 5000. I'm basing this on running through turns in third gear between 4500 and 6000 - sustained driving, not just quick blasts through first and second.

Aegir

No change in normal driving. Deeper tone at full throttle around 3000 and higher. No hissing.

Aegir

It was a free and easy modification. I'm happy with the initial results and I'll see how it dyno's. If I decide to add a CAI in the future, the hard work is done.

The AEM dyno you posted is impressive, especially the torque!

PeterUbers

iTrader: (1)

You should consider a hi-flow FRAM or K&N filter now .. you'd probably clinch the effect you've desired...

Damn good write-up .. awesome pics.. a great read!!!

PeterUbers

iTrader: (1)

I know exactly what the sound difference was for you ... b/c I recall the difference from when I went from a stock TL-S airbox to the Comptech Icebox... the sound was just like yours afterwards: perfectly quiet at idle and light-moderate throttle... midrange DID suffer a tad.. but high-end was nice in terms of growl... didn't notice ANY performance gains.

Your psychological desire to justify your 2 to 3 hour endeavor usually adds 10-15hp in your mind.. but if you're happy, that's the point. I think the sound alone is worth it all!

cliff

took mine out about a month ago, awsome sound, love the roar when vtec kicks in. and the nice rumble growl at 3500. if anyone wants a mean noise and cant spend money, this is your mod

GaleForce

What dyno?

Casper42

Look for a link to a PDF File in this thread. Its the Dyno Results from AEM for the Cold Air on a 2004 TL

flnsx

Dyno doesn’t really work on Cold air boxes or airflow improvements.

You really need to be moving.

1SICKLEX

Sigh, Acura tries hard to beat the rice wrap....

NightRider

Aegir, I thought that you could remove JUST the resonator box and not the entire system. My car is in the shop right now and (no pics, sorry) because of the accident the whole induction system is showing on the car. I was going to have the body shop remove the resonator box, but now might possibly remove the enitre system. I am concerned about the effect on low-midrange torque sans resonator. Do you feel any difference negative or positive in low and mid range?

PeterUbers

iTrader: (1)

LOL!! 20whp and 18lb-ft of torque... that's the biggest crock of sh-t I've ever seen ... just for an air intake???!!

My headers barely got me over 25whp and 20lb-ft of torque on my TypeS

NightRider

Yes, you must consider that they are in a business, the results are to encourage sales and may be biased accordingly. It needs to be tested by a source independant of the production company as a control. One of the mechanics at the dealership told me headers add around 10% horsepower. For just an intake I wouldn't expect much more than around 10HP/10lb-ft.

Aegir

I don't feel any difference at low-mid RPM's.

To just take out the resonator you would have to remove the upper tubing that goes to the filter box from the resonator and bridge the gap with 3" tubing. I don't think it will come out, so you would have to bridge from the "U" at the base of the resonator, which is 3" tubing, to the filter box inlet, which is about 3"x3 3/4" oblong. It could be done...

Aegir

...with one hand, as they profit from it with the other!

Aspector Gadget

Aegir,

Would it be possible, or would it even be useful to leave the duct work? My thinking would be increase cool air flow to the inlet area without restricting the amount of air going into the engine. Another possibility is drilling holes it the siliencer in order to increase the amount of air it can take in.

PeterUbers

iTrader: (1)

In AEM's defense, I did look at their .pdf file for the 2001-2003 TypeS, and their CAI produced the expected 10whp/10lb-ft ... so perhaps there is some merit to their product .. though I'm still very skeptical.

Aegir

Could be. You'd have to try it out - that's part of the fun of it. The traditional thinking is that the ductwork and especially the resonator interfere with airflow. I think drilling would increase the odds of getting weird or whistling type noises.

jackal2001

Every time I see intake mods on Car shows they say to "ALWAYS" go back and adjust you cars computer to adjust for the mods.
AEM must have done this as well to get the extra ponies out of it.
Unfortunately not everyone wants to pay the hundreds of $$$ that these things cost that you will only use one or two times.

pabound

OK, another "beat the dead horse" question. Aegir - removing the silencer, do you now consume engine bay air? Did the silencer/resonator not preferentially induct cooler air, and not the higher-temp engine bay air?

Tell me I am wrong...

NightRider

Good point! That was another concern I had, is our system just air induction or cold air induction? By doing what you did it would get more airflow, but yes the air would be coming more directly from engine heat. Could getting more air but hotter air nullify the effect of this mod?

PeterUbers

iTrader: (1)

Nightrider .. the effect of this mod is mainly the sound... trust me, you ain't gunna get any noticeable power gains from this.

Even with a true cold air induction system, you couldn't discriminate any noticeable power differences.

NightRider

Did you see my last post before posting this? What about power decreases because of hot air from engine instead of cool air from induction?

rets

This is what I thought...

Our engine gets air by three different ways
air from an inlet in the left front fascia
an air by air deflector under your front bumper
air from the front into the engine compartment

The ambient air picked up through an inlet in the left front fascia is the new design from Acura, and air is fed by a duct to the engine air intake, this theoretically will make the combined ambient air cooler than typical engine comaprtment air (Acura claims it could be much as 15 degrees F cooler) depending on your speed.



If the removal of the silencer doesn't come with other setup, I think this only helps improve the suction of the engine instead of reducing the temperature dramatically. Or I could say the more space in the engine bay will get better convection, and the temperature of the engine compartment should be a little cooler than the original setup.

If someone could direct air directly from the left front fascia to the filter and prevent water or any debris hurting the filter or engine, this could be the best while your car is moving. :o






You could see more info in Garage's DIY section... by Bitium & Aegir...

Aegir

My current setup is drawing air from the left fenderwell. The area is shrouded from hotter engine air in the same manner as the stock setup. I had the shrouding off for the pics. Fresh air is coming from the opening in the bumper and from under the car. In the pic where you can see the filter, the camera is being held right by the bumper inlet. The air may be even cooler because the inlet is further from the radiator. Sorry for the speculation - I don't own a OBD scanner to check IAT.

I ran a new Z at lunch, but that story will have to wait. I have an appointment with the dyno in about an hour and have to run. I'll post the outcome.

GaleForce

Sound clip?

PeterUbers

iTrader: (1)

Arguably .. the power gained from increased flow would counteract the power lost from increased temperature of the air. The Frankencar intake for the Nissan Maxima is designed such that only a high-flow filter attaches directly to the throttle body. And it makes great high-end power, at the loss of some low-end power. And that is drawing pure hot engine air. So basically, on a cold day, the air flow will prevail, and on a hot day, the hot engine heat will kill power.

The best bet would be to design a custom piece of air tubing attached to a high-flow filter and then to the throttle body that would actually just be a straight-shot of tubing into the fender where it could snag cool air all day long from the wheel well.

PeterUbers

iTrader: (1)

That's one of the most restrictive set-ups I've ever seen -- it only promotes turbulence which kills some of the power gains. You want good laminar flow ideally, and most well-engineering CAI products have very few curves and kinks in their tubing to eliminate all this.. About the only gains I see for the '04TL's stock inductions system compared to the induction system i yanked from my TL-S is that there are more "curves", compared w/ all the angled kinks in the TL-S setup, and yes, there are two more air entry points -- AND the air inlet in the front air damn isn't blocked by a "damn" foglight like the TL-S did.

Aegir

...and it doesn't always tell you what you want to hear either. Here's the dyno:



Test conditions:
82F, 245/40/18 tires @ 38psi, 4th gear pull, a new Honda air filter was installed prior to the test.
Best of three pulls.
Car was run 'off the street' for the first two pulls. Cooled about five minutes with the fans, then run again. Third pull was the best, but within 2hp of the first two.

My conclusions (please feel free to share yours):
1. If you are looking for power, I do not think this is a good mod. Compared to other stock 6MT dynos, I don't see a gain - certainly not along the lines of what CAI's are advertised to provide. The throatier intake note is a plus, but IMO not enough to justify the work. PeterUbers, you were right on the money.

2. The TL clearly makes power all the way up to the redline. I think the first TOV dyno was an anomolie. Every dyno I've seen after that has power increasing to the redline.

3. Torque curve on this engine amazes me.

4. The TL sounds incredible on the dyno at full tilt! Wow! That alone was worth the price of admission.

I wish my mod had produced more power, but I think it was still a worthwhile endeavor. I got to play with my car and learn more about it, it wasn't too expensive, and it got me out to the dyno shop. Hey, someone had to do it and now we all know how it turned out.

Future plans are to move to a true CAI. With the resonator out, it should be an easy install. My preference would be an IceBox (I like the OEM look and easy filter access), but there isn't one. The dyno posted for the AEM CAI seems too good to be true, so I may be doing some independent testing on it if I can get my hands on one in a reasonable time frame.

flnsx

What a great write up!

Man! I wish I lived in California so I could have gone with you.

Thanks for doing much needed R and D for our cars!

What if you had a K&N installed instead of the stock air filter.

Cheers to you mate!